Single-polarization, flared-notch radiators are typically designed by optimizing the radiation performance of the element in one plane (co-polarized), without regard to its performance characteristics in the plane orthogonal to the radiator (cross-polarized). For a wave impinging upon an antenna comprised of these flared-notch radiators, this design approach results in a radiator that provides maximum absorption of the co-polarized component of the incident wave, but minimal absorption of the cross-polarized component from the radiator tips.
It would therefore be an advantage to provide a technique to improve this cross-polarization absorption component.